An estimation of a traffic situation, such as a traffic volume, or the like of people, vehicles, or the like on a road, a track, a facility, or the like is being made. The estimation is performed using sensor data that was observed by sensors capable of observing information regarding movement of moving bodies, such as people, vehicles, or the like. An example of the sensor is a global positioning system (GPS) capable of observing the movement trajectory of a moving body. Other examples of the sensor is a road sensor for the system under the trademark “Vehicle Information and Communication System” (VICS) that is capable of observing the number of moving bodies that pass through a fixed location, and a ticket gate that supports a traffic system IC card.
One of proposed technologies for estimating a traffic situation is a technique for estimating a traveling time in each link on a road network by using the traffic information obtained by the information from road sensors and traffic information transmitted from a running vehicle. In this technique, the estimated value of the traveling time is α times the average speed of a vehicle in each link when information from a running vehicle is obtained. In this regard, α is the actual distance of a road section represented by a link length or a link. Also, the estimated value of the traveling time is a times the average speed of a vehicle in each link when information is obtained from a road sensor. Further, in a link where both the information from a running vehicle and the information from a road sensor are obtained, the estimated value of the traveling time is the weighted sum of the estimated value calculated based on the information from a running vehicle and the estimated value calculated based on the information from a road sensor.
Also, there is proposed a method for solving an integer programming problem under the constraint condition which is the traffic flow rate observed by each sensor located at each site. In the method, a variable is the traffic flow rate for each path on a time-space network obtained by expanding a network representing a traffic system in the time axis. In this method, the traffic flow rate is obtained for a path having actual passage results of people in the past.
As patent literature, a related-art technique is disclosed in Japanese Laid-open Patent Publication No. 2004-29871.
As nonpatent literature, a related-art technique is disclosed in Shunnji UMETANI, Tooru KUMANO, Takashi HASUIKE, Hiroshi MORITA, “Estimation of movement history of people based on observation information”, CSIS DAYS 2014 Research Abstracts, 2014, pp. 26.